1. Field of the Invention
The present invention relates to the field of image processing, and more particularly relates to an apparatus, a method, and a system for automatically identifying a laser spot and locating coordinates of the laser spot in an image.
2. Description of the Related Art
With requirements of users and development of technologies, a virtual whiteboard system or a virtual presentation system, in which a laser pointer is adopted to be as an input device, has been developed; by using the virtual whiteboard system or the virtual presentation system, an image is projected onto a screen.
For example, an apparatus for locating a laser spot is disclosed in the below cited reference No. 1; a presentation system using a laser pointer is disclosed in the below cited reference No. 2; and a technique of realizing interaction by employing a laser pointer and a camera is proposed in the below cited reference No. 3.
However, in the above-mentioned conventional techniques, there are still various problems of how to automatically identify the laser spot and locate the coordinates of the laser spot.
For example, in the technique disclosed in the below cited reference No. 1, it is necessary to utilize uncalled-for hardware to locate the coordinates of the laser spot; as a result, complexity of the system is increased, and then cost of the system is increased too.
Furthermore, in the technique disclosed in the below cited reference No. 2, visible light is not able to be detected, and it is necessary to employ uncalled-for hardware to support the presentation system; as a result, complexity and cost of the system are increased.
In addition, in the technique proposed in the below cited reference No. 3, only the brightest portion of the laser spot is of concern; as a result, accuracy of the detection result may be reduced, and a specific exposure condition is required, i.e., a function of automatically adjusting brightness in the camera has to be turned off.
Therefore it would be desirable to provide a technique of being able to accurately identify a laser spot and locate coordinates of the laser spot in an image without adopting uncalled-for hardware, for example, the uncalled-for hardware mentioned above.
Cited Reference No. 1: US Patent Application Publication No. 20060284832 A1
Cited Reference No. 2: US Patent Application Publication No. 20030132912 A1
Cited Reference No. 3: Dan R. Olsen Jr. and Travis Nielsen, Laser pointer Interaction